The invention relates to a bottle teat, especially for infants and small children.
Bottle teats are used to administer milk and other liquid nutrition, especially to infants and small children. Bottle teats have a hollow nipple with a through-hole for liquid nutrition. The nipple is connected at the bottom as a single part to a hollow nipple sleeve. At the bottom, the nipple sleeve has an annular nipple flange. The cross-section of the nipple is tailored to the mouth of a child. In the area of the nipple sleeve, the cross-section expands toward the nipple flange to the cross-section of a fastening edge of a bottle. The nipple is fastened by means of a fastening ring to the fastening edge of the bottle. The fastening ring has a cylindrical cover with fastening means to be fastened to the fastening means of a bottle. Frequently, the fastening means are threads on the inner circumference of the cover and on the outer cover of the bottle. Furthermore, the fastening ring has a downward-projecting, annular-disc-shaped ring flange that overlaps the nipple flange and presses against the fastening edge of the bottle. In response to suction, a vacuum arises in the bottle that makes it difficult to withdraw the liquid. The bottle teat can collapse from the vacuum, causing the nipple to slip into the bottle. To prevent this, bottle teats have a ventilation valve. The ventilation valve opens when a certain vacuum predominates in the bottle. This causes the pressure to adjust to the surroundings.
DE 197 39 911 C5, the entire contents of which is incorporated herein by reference, describes a bottle teat of the aforementioned type and the fastening of the bottle teat by means of a threaded ring to a bottle. With this bottle teat, the ventilation valve is a slot valve that is arranged in a recess in a side of the sleeve.
WO 2009/087077, the entire contents of which is incorporated herein by reference, A1 describes a bottle teat having a plurality of drinking slits that are arranged in the sides of an imaginary polygon. The vent valve of this bottle teat is a slot valve arranged in a recess. The bottle teat is made of a soft elastic material.
According to one embodiment, this is natural rubber, or silicone, or a thermoplastic elastomer (TPE). The bottle teat can for example be made by dipping a molded body in a latex suspension, or by injection molding and subsequently incorporating the slots by means of knives.
DE 299 06 849 U1, the entire contents of which is incorporated herein by reference, describes another bottle teat having a ventilation valve in a recess in the side of the sleeve. The recess has substantially flat, opposing sidewalls that are connected to each other in the base of a recess across a narrow section in the wall. After the section is opened by means of a screwdriver, fork, etc., the side walls can be pressed against each other by the liquid in the bottle.
The known bottle slot valves are difficult to produce since they have to be provided with a slot in an additional production step. An additional disadvantage is that the sealing lips delimited by the slot only rest against each other with a slight amount of pressure; consequently, the lip valve opens when a vacuum is applied that can be less than the vacuum exerted by a child while nursing.
Furthermore, nipple teats are known with a ventilation valve between the nipple flange and threaded ring. DE 10 2005 006 768, the entire contents of which is incorporated herein by reference, A1 discloses such a bottle teat that, in the nipple flange, has a valve opening that narrows toward the ring flange of the threaded ring.
On the top side, the nipple flange has an annular elevation which engages in a groove in a peripheral, bottom base surface of the threaded ring. In the outer side, the nipple sleeve has a recess that extends to the nipple flange and forms a ventilation channel. The outer edge area of the nipple flange is clamped between the fastening edge and ring flange. Provided that a vacuum predominates in the bottle, the inner part of the nipple flange can move downward, causing the elevation to move away from the base of the groove. Consequently, the pressure can be equalized through the ventilation channel, the gap between the ring flange and nipple flange, and the valve opening.
This design is complicated to produce and difficult to clean. In addition, an axial force acting on the bottle teat can open the ventilation valve which prevents a vacuum from building in the bottle.
A similar design is known from US 2007/0102388, the entire contents of which are incorporated herein by reference.
Nipple teats with lip valves in the bottom side of a nipple flange are known from US 2005/0252875 A1, the entire contents of which is incorporated herein by reference, WO 2006/103379 A1, the entire contents of which is incorporated herein by reference, DE 202 04 357 U1, the entire contents of which is incorporated herein by reference, and US 2003/0106872 A1, the entire contents of which is incorporated herein by reference. These bottle teats are produced in an injection molding procedure. For production reasons, the sealing lips lie against each other without initial tension so that they can be easily opened by a vacuum. The pressure is equalized when the valve is opened through a gap between the top side of the nipple flange and the bottom side of the ring flange. When liquid lies against the side surfaces of the ventilation valve, they are pressed together and the liquid is prevented from exiting. The two last-cited documents describe bottled teats in which the lip valve is integrated in the wall of the nipple flange.
Against this background, an object of the invention is to create a bottle teat that is easy to produce and enables the opening pressure of the ventilation valve to be specified.